Modern communication technology utilizes cables, such as fiber optic cables, most often positioned in a conduit or casing which is buried underground. The installation of such an underground cabling network is a tedious and expensive project. First, usually a trench must be dug and then the conduit or casing, typically of two to four inches in diameter and oftentimes extending for miles in length, is positioned in the trench. The communications cable is then installed in the casing, either by pulling or pushing the same therethrough. The trench is then filled and the communications network is ready to be utilized, being housed in the casing safe from the environment of water, gnawing animals and the like.
One of the problems with these systems is that a casing can usually only carry one cable which is positioned therein in a random, sinuous path thereby essentially prohibiting another cable from being readily installed in the existing casing. Thus, if at a later date the communications system needs to be expanded, as by the addition of another cable, the entire installation process needs to be repeated--at a redundant expense.
One solution to the problem, which has been suggested, is to introduce a strip of material into the existing casing which effectively pushes the existing cable to one side in the casing thereby creating a second chamber in the casing for the unobstructed installation of a second cable. Such a procedure, however, first requires the separate manufacture of the strip material, and then requires the separate installation thereof in the field in the existing underground casing. Moreover, this installation in and of itself can be quite tedious and time consuming inasmuch as first a rope must be blown or otherwise introduced into the casing along its entire length. Then the strip is attached to the rope and pulled with sufficient force to move the existing cable aside and navigate all of the bends and turns normally encountered in the network--while at the same time taking care that the existing cable is not damaged. Finally, a new cable must then be positioned in the casing to complete the project.
It has also been proposed to extrude a casing, which is typically formed of a polyvinylchloride material, with a diametric bar extending thereacross to permanently divide the casing into two semicircular halves. However, such complicates the manufacturing process necessitating the development of special temperature parameters so that the casing cools at the same rate as the bar extending across the inside of the casing. Even when such care in manufacturing is taken to the best extent practical, often the bar will shrink faster causing the casing to take on an undesirable elliptical shape. Finally, while this permanently divided casing does solve some of the problems of the prior art, when a cable is being installed in this casing, movement of the cable is often impeded as it engages the permanent Junction of the bar and the inside of the casing. That is, the cable will tend to get stuck on these junctions, especially when many turns are encountered, which not only impedes the facile installation of the cable, but can also tend to damage or abrade the cable making it unsuitable for its intended use.
Thus, the need still exists for an economically manufactured divided cable conduit assembly into which more than one cable can be readily and efficiently installed without the likelihood of damage thereto.